Pruitt’s comments come after conservative groups petitioned him to reconsider the 2009 endangerment finding that gave EPA the power to issue global warming rules. Pruitt said there was a “breach of process” in issuing the finding.

“The work done in 2009 was accelerated by the agency,” Pruitt said in a House Committee on Energy and Commerce hearing in response to questions from Texas GOP Rep. Joe Barton.

“In fact, there was something done in 2009 that, in my estimation, was never done since and not done before that event where they took work from the UN IPCC and transported it to the agency and adopted that as the core of the finding,” Pruitt said.

At least two groups, the Competitive Enterprise Institute (CEI) and Concerned Household Electricity Consumers Council, have filed petitions with EPA to reconsider the endangerment finding.

CEI sent a letter to Pruitt in October signed by “60 climate and health experts” asking Pruitt to respond to the group’s endangerment finding petition.

“As our petition points out, there are huge problems with the computer models on which the Endangerment Finding was based, which means our government’s climate policy rests on bad science,” Sam Kazman, CEI’s general counsel, said in a statement.

Pruitt’s comments in the hearing where the first time the EPA head spoke about the endangerment finding for months. Environmentalists oppose removing the finding, and some Republicans say tackling it would only take the focus off the policies in need of reform.

“So, there was a breach of process that occurred in 2009 that many believe was not handled the proper way, but the Mass v EPA decision and the processes that followed involved both the Bush and Obama administrations and that process was, again in 2009, short-shrifted,” Pruitt said in the hearing.

Pruitt also told Barton he planned on announcing a “red-blue team” exercise on climate science early next year. Pruitt said he wanted an open, transparent debate on global warming science.

“It hasn’t happened at the agency,” Pruitt said. “As I indicated, the agency borrowed the work product of a third party, and we need to ensure that that discussion occurred, and it occurs in a way that the American people know that an objective transparent review is taking place.”